Extracting caffein from coffee.



H. TRILLICH. EXTBAGTING IGAFFEIN FROM COFFEE. APPLICATION FILED APR. 15, 1909.

Patented Mar. 29,1910.

five/21 0f Ham-6J1; zz/17,. W M ff? I UNITED HEINRICH TRILLICH, 0F MUNICH, GERMANY.

EXTRACTING CAFFEIN FROM COFFEE.

Specification of Letters Patent.

Application filed April 15, 1909. Serial No. 490,162.

To all whom it may concern: A

Be it known that I, HEINRICH TRILLICH, a subject of the Kin of Bavaria, residing at 21 Prinzregentenp atz, Munich, Bavaria,

Germany, have invented certain new and useful Improvements in Processes of Extracting Cafi'ein from Coffee or from Similar Materials which Contain Cafi'ein, of which the following is a specification.

My invention aims to provide a process of extracting cafl'ein from raw ungroundcoffee and from similar materials which contam cafielmwhich very effective and furnlshes, within a comparatlvely short time, a

product which is sufiiciently freed from caffein, but which does not lose any aromatic or other useful ingredients of the coffee.

As is known, it is not possible to extract cafl'ein' from raw coffee beans thoroughly,

even when using the best dissolvents ofcaflein, which leave undissolved the aromatic and other useful ingredients of the coffee, and continuing the extracting for two or three days, for two reasons, first due partly to the existence in the beans of combinations between cafi'ein and tannic matters, which belong, as is well known, to the natural cons'tituents of coffee, and second to the poor penetration of the dissolvent into the beans.

My improved process aims at dissociating the combinations of caflein and tannin-containing substances by effecting a sufficient penetration of the dissolvent into the coffee beans. In order to attain this end, I propose to cover the coffee beans in their raw state, and similar materials which contain cafl'ein, with dissolvents such as acetic ether, benzol, carbon tetrachlorid, ethane tetrachlorid, benzol dichlorid, chloroform, sulfuric ether, dichlorhydrin, epichlorhydrin, carbon sulfid, ethylene trichlorid, and which leave undissolved the aromatic and other useful ingredients of the coffee, and to produce a pressure of from one to two atmos-' pheres-for instance by means of introducing steam into an autoclave boiler which contains the cofl'ee beans covered by the dissolvent, whereby'the latter is vaporized and owing to the non-escape of the vapors a hi h internal pressure is produced causing t e eans to dissociate the caffein and tannic acid combinations to facilitate the cafi'ein extraction.

Hot acetic etheris preferred as a dissolvent of the cafl'ein, because it is considered the most effective dissolvent of cafi'ein and does not leave a bad smell in the product, as it is to be found with benzol, chloroform and the like.

It occurs sometimes that certain characters of coffee cannot be thoroughly extracted by a single extract-ion, and therefore it has been found necessary to alternate the production of the pressure and the extractmg.

After having performed the extraction, the residues of the dissolvent which adhere to the coffee, are evaporated in the usual manner.

Referring to the drawing, 1) denotes an extraction vessel surrounded by heating jacket a and is furthermore rovided near its bottom with'a sieve d. T e vessel 6 is adapted to receive the coffee beans 0. Communicating with the bottom of the vessel b is a siphon conduit which opens into the still 6, the latter being surrounded by the heating jacket f. Pro ecting from the still '6 1s a pipe g which opens at Its upper end in a coil 5 mounted in a cooler h. The coil i is connected with the upper end of the vessel 1) by a pipe is provided with a cut-off g. Projecting from the upper end of the vessel Z) is an" outlet pipe n having a cut-off m and interposed between the cut-off m and the vesse b is a pressure gage o.

The extracting medium flows from the coil 2' into the receptacle 1) and onto the beans 0 and is carried over by the siphon conduit p into the still e, from which it extends up the pipe 9 and returns to the coil 2'. The

Patented Mar. 29, 1910.

conduit pipe p is provided with a cutoff 1'.

If the cut-ofis m, g, and 1' are closed, there can be generated in the vessel 1) by the heating thereof through the medium of aheating jacket a, a sufliciently high internal pressure for use in connection with the method. 'The pressure can be indicated by the gage o. By opening the cut-off m the pressure within the vessel 6 can be regulated.

A specific example carrying out the process is as follows: Into the vessel 6 is placed 40 kg. of raw coffee beans, without the beans being subjected to anyrprevious treatment,

that is to say, the een beans are removed from the-bags in w ich they are shi ped in from the plantation, such quantity 0 beans fills the vessel b to a point near the top thereof. After the beans have been placed in the vessel b acetic ether is run into the vessel, the tptiantity of the acetic ether being such that a er absorption by the beans the as the upper bend of the siphon conduit p,

the quantity of the acetic ether being ap-' proximately 70 liters.- liters of acetic acid is also placed in the still 6, then the fill ing openings of the vessel 6 and still 6 are closed.- All of the valves of the vessel 1) are closed tight, that is the valves g, m and r, whereupon steam is introduced into the jacket a. Supplying of steam to the jacket a brings the acetic ether in the vessel 6 to a boil or in other words vaporizes the ether, the generated vapors in consequence of the closed valves cannot escape, under such conditions there arises in the vessel b inabout thirty minutes an internal pressure, whose height can be read by the gage 0. The pressure due to the generation in the vapors in the closed vessel 1) is'allowed torise to a point of from one to two atmos pheres and kept at the desired point for an hour due to the regulation of the steam supply. The generation of the vapors in the manner as stated and. holding them at the pressure desired dissociates the combinations of caiiein and tannin-containing substances and efi'ects a sufficient penetration of solvent into the coffee beans, whereby the extraction of the cafi'ein is facilitated when the beans are subjected to extraction by a suitable dissolvent. After the pressure has been maintained for about an hour at the point desired, the valve 9 is opened, and the vapors escape through the plpe kinto the cooling pipe 5 and they are condensed and fiow'back into the vessel 1). Steam is then supplied to the steam jacket of the still 0 so that the acetic ether therein will be heated and the vapors generated by such action will escape through the pipe g and be condensed in the cooling pipe 91 and flow through the pipe is into the vessel 1). In the meanwhile the valve 1' is opened and as soon as the acetic ether in the siphon conduit p has exceeded the highest point of the siphon, the siphon begins to pull and withdraws the acetic ether contained in the vessel Z) and discharges it into the still e, naturally including the disi solved caffein, while the coffee beans are held back by the perforated bottom at of the vessel b. The acetic ether that has been drawn jected to the siphoning action for three hours at ordinary temperature. The heating of the steam jacket 7 is then discontinued and the valve 7' closed after the last remainsof the acetic ether has been run 011?. The

closed vessel raw coifee beans submerged in a dissolvent of cafiein which leaves undissolved the aromatic and other valuable constituents of the beans, then subjecting the mass to heat whereby the dissolvent will vaporize and the vapors create in the vessel so as to causethe dissolvent to thoroughly penetrate the beans to dissociate the cafi'ein a pressure of from one to two atmospheres taining caffein, consisting in placing in a closed vessel raw coffee beans submerged in a dissolvent of cafiein which leaves undissolved the aromatic and other valuable constituents of the beans, then subjecting the mass to heat whereby the dissolvent will vaporize and the vapors create in the vessel a pressure of from one to two atmospheres so as to cause the dissolvent to thoroughly penetrate the beans to dissociate the cafiein and tannin-containing substances whereby the extraction of the caflein will be facilitated, then extracting the cafiein which has been dissociated during the subjecting of the beans to pressure, and then evaporating the dissolvent adhering to the .cofl'ee beans.

3 In a process of extracting cafl'ein from raw coffee beans and similar materials containing cafi'ein placing in a closed vessel raw cofi'ee beans submerged in a dissolvent of caifein substantially such as described, and then subjecting the mass to heat wherebythe dissolvent will be vaporized creating within the vessel a pressure of from one to two atmospheres causing thereby the thorough penetration of the solvent into the beans to dissociate the combinations of cafiein and tannin-containing substances.

In testimony whereof I aflix my signatui'e.

HEINRICH TRILLICH.

In the presence of r LoUIs I. MUELLER, MATHJLDE K, 

